Case Of the Week (COW) 07 April 2013
Answer:
REVERSE HILL SACH AND REVERSE BANKART LESION
Findings:
Focal STIR hyperintensities are seen in anteromedial aspect of the superior humeral head , consistent with Reverse Hill Sach lesion. There is postero inferior glenoid labral avulsion associated with, small chip fracture, consistent with Reverse Bankart lesion. These features reflect a Posterior Labrocapsular complex injury.
Discussion:
Anterior instability is the most common type of glenohumeral instability, However it is important to be aware of diagnosis of posterior instability especially after athletic injuries . Reverse Hill-Sachs fracture is an impaction fracture of the anteromedial humeral head after posterior humeral dislocation. A coexisting posterior labrum and capsule complex lesion is a cause for instability. In the reverse Bankart lesion, the posteroinferior labrum is detached from its glenoid attachment and there is an avulsive tear of the posterior scapular periosteum as well. This results in increased laxity of the posterior band of the inferior glenohumeral ligament .
REF: AJR:March 2009, Volume 192, Number 3 Imaging Signs of Posterior Glenohumeral Instability
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai
Answer:
REVERSE HILL SACH AND REVERSE BANKART LESION
Findings:
Focal STIR hyperintensities are seen in anteromedial aspect of the superior humeral head , consistent with Reverse Hill Sach lesion. There is postero inferior glenoid labral avulsion associated with, small chip fracture, consistent with Reverse Bankart lesion. These features reflect a Posterior Labrocapsular complex injury.
Discussion:
Anterior instability is the most common type of glenohumeral instability, However it is important to be aware of diagnosis of posterior instability especially after athletic injuries . Reverse Hill-Sachs fracture is an impaction fracture of the anteromedial humeral head after posterior humeral dislocation. A coexisting posterior labrum and capsule complex lesion is a cause for instability. In the reverse Bankart lesion, the posteroinferior labrum is detached from its glenoid attachment and there is an avulsive tear of the posterior scapular periosteum as well. This results in increased laxity of the posterior band of the inferior glenohumeral ligament .
REF: AJR:March 2009, Volume 192, Number 3 Imaging Signs of Posterior Glenohumeral Instability
Contributed By:
Dr. Babu Peter MD, DNB
Associate Professor, Barnard Institute of Radiology, Chennai
Senior Consultant Radiologist, Aarthi Scans, Chennai